Many people agree that Honesty is the best policy.
Billy Ray may be homeless, but that does not mean he is not honest. It's hard to come by such an honest person; that ring was not any ordinary ring. It meant a lot to Sarah and to show how grateful she is, she went all the way to help him by setting up a fund, as a way of repaying his kindness and honesty.
Most people would have just kept the ring and sold it to cash in for their own use. It would have gone a long way if Billy Ray had done that, but he did not.
Many people view our homeless friends as dishonest, outcasts of society, not worth a second chance. Deep down inside, they are just like any human being, like you and me. They just happen to be unfortunate not to have the means to support their livelihood according to society standards.